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Topic: My webster build (Read 21187 times)

2 months ago I could hardly spell "lathe" but I wanted a new hobby, so I found a lightly used, but broken 7x12 on craigslist for $200 with some tooling, bought a replacement board from LMS, and started making swarf. The internet is a great place to find ideas and how to's so I started searching. I came across Joe Websters free 4 stroke plans: http://home.comcast.net/~webster_engines/... and I was off.

I first made a bolt... and was pretty proud of it, then a little wobbler, it worked well, but I wanted something that made fumes.... so I started on the Webster. Luckily there is a Metal Supermarket 4 miles from my house so I purchased the raw stock needed for the Webster and started turning.

The cylinder and piston were first, then the head. It was fun over Christmas to show my friends and family what I had created. Everyday I made another piece and I got a little closer to "first pop". It happened on January 9th, after 8 build days in the shop.

All the parts shown with the exception of the bearings, plug, bolts, ignition coil, and finned flywheel were made from scratch, some based on the basic plans. I did not want to go the points and condenser route because of the luggage you have to haul around in order to run the motor. I had found a dead weedeater on the side of the road 2 years ago and I tossed it in the "to be used someday" pile. I works VERY well and I plan to use this type of ignition in the future because it is so reliable and cheap.

The vapor carb is based on Jan Ridders idea, but completely designed and built by myself. I used a carb off my old RC10 GT nitro car and it worked ok, but was a pain to adjust and not reliable, so I use the vapor card exclusively now. I can adjust the mixture with a turn of a long nut that covers and uncovers a hole on the intake tube.

I am currently running straight Coleman fuel with a few drops of marvel mystery oil, but have used nitro methane, denatured alcohol, 87 oct gas, butane, propane, rubbing alcohol, and mapp gas (stinks...). the coleman fuel can be run in the house for short times and it has a pleasant odor like I am camping...

The ignition timing can be adjusted by moving the coil up and down thus changing the spark from 20 degrees BTDC to 20 degrees ATDC. A neat effect of this is that you can adjust the idle from 1000 RPM to 4000 RPM just by changing the timing.

It will start with a swift turn of the flywheel, but this gets old quick so I installed a one way bearing and nut from an old RC rope starter and I can use my drill with a 12mm socket to start it. It just takes 1 or 2 revolutions to fire and then revs to full RPM.

I might add a rope starter pulley and a PTO pulley some day, but for now I am done with modifications and am starting on Jan Ridders OTTO engine.

first pop: January 9th, 2011. I was afraid to adjust it for a few hours....

A close up of the valve train without the flywheel installed. The gears were made from aluminum bar stock modeled after the 20 and 40 tooth gears from my 7x12 mini lathe. I made an arbor and mounted the blank to the plastic gears and then cut the tooth profiles with a dremel grinder. Turned out pretty good, I think. The cam was made from a 1/2 inch bolt that I turned down to the high OD of the cam and then carefully sanded away the small OD with my 36x4 inch belt sander. I had to adjust the duration after it was mounted on the gear, so I used a file and a sanding disk to knock it down.

the finished motor running. normal running speed is about 3000 RPM and can be changed with the ignition timing and fuel mixture. The mixture from the vapor carb is adjusted by turning a piece of threaded tubing that covers a slot in the intake tube, thus adding air to the 14 to 1 fuel vapor in the tank.

The motor idles about 1000 RPM because the ignition system needs that to generate a spark and will go up to 4000 RPM just by adjusting the timing from 20 DEG ATDC to 20 DEG BTDC. The Vitron o-ring gets a little sticky at high heat from high RPM's, so I have to squirt a little WD40 in the cylinder to lube it back up. With low RPM's the oil in the fuel does fine keeping it cool and lubed. I might install an oiler someday, but it is very easy to just spray a light oil squirt every few minutes...

« Last Edit: February 14, 2011, 01:35:44 PM by dbvandy »

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"if you can pay someone to do it, then you can do it... just might cost more and take longer." ~Grandpa Vanderbilt

Very good looking Webster. Really like the finish. Looks like you have come to know your equipment pretty well. Only 8 days of building??. How many hours per day?

Spent a lot of time in Georgia years ago. Ft Benning, Ft Stewart, Cusseta, Columbus. Welcome to the forum

We like lots of pictures (you have done that) and videos. Welcome again Ray

The 8 days were over 2 weeks because of the holidays and got me to the first pop day January 9th. I spent 3-6 hours down in the shop, sometimes spending a ton of time making "sample" pieces, but not too many...

I have always been handy and have used my drill press as a poor mans lathe many times. Currently I am using it as a milling machine with a very well seated chuck and an x-y compound vise... works ok, just have to take it slow.

The Webster just got all polished pretty 2 days ago via a new grinder and a 6 inch buffing wheel... I like it to look like jewelry.

It has been very rewarding to see it come to life and to show my friends and family what I have been working on... the number one question I am asked is "what do you do with it?" to which I reply... "show it to you..."

« Last Edit: February 14, 2011, 02:42:07 PM by dbvandy »

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"if you can pay someone to do it, then you can do it... just might cost more and take longer." ~Grandpa Vanderbilt

Very nice example. Strangely I was asking questions about these little ignition modules in another post. The thinking was that it could be used on a model scale but now we have 1st hand proof. Like the novel method of altering the ignition timing too. Some of the really old cars used to have an advance / retard lever on the dashboard. Probably as they didn't have things like vacuum advance in those days. I love the fact that like Bogs' minimag it's a self contained unit. Otherwise you need a battery and a circuit or worse still, a battery, points, coil, condensor etc! It's also good to see yet another example of Jan Ridders vapour carb working reliably.

Well done.

Chris, still watching yours avidly - I reckon you've done the hardest bit - just keep being methodical and plugging away - you've made gears before that would have worked so I'm not worried about that in the slightest. Everybody works at their own pace, you saw when I started my two 'poppin' engines - a year later and I still only have 1 and a box of bits!

I`m building one of these, my build log is on the forum, and I must have spent more time just building and attempting a gear (still not done it!) than you have on the entire engine. I`m selling up.

Chris

Chris, Don't ever give up! I was just about to make a big gear hobbing and indexing mount for my mini lathe cross slide with x and y adjusting and a cutter to put in the three jaw, etc, etc, etc, when I decided that a little hand work was easier than days making tooling. The aluminum gears mesh well and have worn into each other perfectly. I had to adjust where the "stock" webster mounting holes were into the crank support because I was not using the purchased gears, but the backlash is about perfect and the gears make little noise when runing.

I will put some pics together tonight demonstrating what I did to cut the gears. If you have a dremel and a small cutting disk, it is just shaping one tooth at a time. even if you do not have a gear to model after, you can bisect the blank 10 times and you have 20 teeth, 20 times you have 40 teeth. There is nothing magical about the 20 or 40, just that it is a 2:1 ratio. you can use the dimensions in the plans for your blanks.

Doug

« Last Edit: February 14, 2011, 03:05:03 PM by dbvandy »

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"if you can pay someone to do it, then you can do it... just might cost more and take longer." ~Grandpa Vanderbilt

Here is what I did to cut the gears. The actual blank for the 40 tooth on the motor was thicker and had a small hub for mounting the cam, but you will get the idea (I had some 3/16 inch plate laying around...)

I turned the blank to the correct OD for the 40 tooth gear that I was copying from the change gears on my 7x12. If you don't have a gear to copy, you can easily cut a circle into 40 even slices buy using excel and putting in 40 1's then pie graphing it. presto... 40 even divisions, you can see the printed pie graph in the pic with all the parts. I did not need to do this for this build, but have used this in the past for other times I needed to divide a circle. Then you double tape it to the blank, centering needs to be very close, but perfection is not critical. You could tape it up before you cut the ID in the blank and it would be perfect...

I turned an arbor to match the ID of my sample gear and drilled the same ID into the gear blank. (Later, after the gear was cut, I chucked it back up on the finished OD and turned the ID to match my bearings and the cam hub OD to match the ID of the cam.)

Then all you have to do is start cutting teeth with the cutoff wheel. I chucked mine up in my lathe (and put some shop towels down to protect the ways) just because it was easier to hold the Dremel steady when I rested my arms on the table the lathe sits on. The 20 tooth was done first (and then a large piece was pressed over its hub part so I had a place to put in the set screws). You can see where I got a little deep by the cuts in the washer on my arbor. That was during the "learning phase" when I was trying to do it with a file. (bad idea, no control and takes FOR-EV-ER!!!) 45 minutes and 6 teeth later is when I decided to use the Dremel. Great decision.... it only took about 15 minutes after that to finish the 20 tooth. Then I made the 40 tooth with the same process. I did then go back with a small hand file to even out the teeth and make them pretty.

I had a sample gear so I could duplicate the depth and profile radius of curvature, but for this motor it is not SUPER critical as it is low speed and next to zero pressure on the tooth face. Just look at any other gear and try to match the basic shape. You could also look online and there are programs that tell you how deep the tooth should be and you could put that dimension and the OD dimension on the pie graph with a compass before you mount it to the blank.

This might not be the way a "real" machinist would do it, but without making a ton of tooling and lacking a true milling machine and a rotary table, this worked just fine for me. Total time for the three teeth shown was about a minute of cutting.

OK after seeing the pics and reading this thread, I'm selling all my equipment... I feel quite inadiqute, and I have been modeling for years.that project for a complete beginner has to take first prize.Well done.

Thanks for all nice comments guys! I have always been pretty handy and live my life by the motto that my grandfather taught me... "if you can pay someone to do it, you can do it... might just cost more and take longer." The Webster is not perfect, but I learned a lot along the way and have used that knowledge on the Otto build. I like shiny.

Thanks again!

Doug

Logged

"if you can pay someone to do it, then you can do it... just might cost more and take longer." ~Grandpa Vanderbilt

Thanks for all nice comments guys! I have always been pretty handy and live my life by the motto that my grandfather taught me... "if you can pay someone to do it, you can do it... might just cost more and take longer." The Webster is not perfect, but I learned a lot along the way and have used that knowledge on the Otto build. I like shiny.

Thanks again!

Doug

Doug

Smart man your Grandfather. I suspect that he taught you much more than just that saying. You have shown a fine example of what one can do if they put their mind to it and use a good dose of patience. I believe that your Grandfather would be very proud of you for what you have accomplished with this engine. I am looking forward to seeing more of your work in the future.

Cheers

Don

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Good, better, best.Never let it rest,'til your good is better,and your better best

Smart man your Grandfather. I suspect that he taught you much more than just that saying. You have shown a fine example of what one can do if they put their mind to it and use a good dose of patience. I believe that your Grandfather would be very proud of you for what you have accomplished with this engine. I am looking forward to seeing more of your work in the future.

Cheers

Don

Yea... miss him tons... just in case you have not seen... the newest addition to Vandy Engine Worx...